The NEW Build Your Own Arcade Controls
Arcade Collecting => Miscellaneous Arcade Talk => Topic started by: SirPeale on August 22, 2008, 05:55:55 am
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There are different ways I could go about it, but I like the look of this one here:
http://www.robotron-2084.co.uk/techwilliams4164.html
The only thing I haven't figured out is how he tied the +5V to where the +12V used to be. If there were wires that'd be easy, but there are no wires.
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Its difficult to see.... But there is some purple jumper wire soldered in there. I think the extra length is just tucked in when the connectors are brought together.
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There are different ways I could go about it, but I like the look of this one here:
http://www.robotron-2084.co.uk/techwilliams4164.html
The only thing I haven't figured out is how he tied the +5V to where the +12V used to be. If there were wires that'd be easy, but there are no wires.
Pin 8 of a 4164 needs +5 as it's supply voltage. This is +12 on a 4116, hence I looped the +5 from the 5 volt supply to the 12 volt reg pin.
A careful study of the schematics reveals....
+5 used all over the place -5 only used by RAM
+12 reg only used by RAM
Could be wrong, but it looks like he just fed the +12v pin on the header +5v instead.
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I got that much, Chad; I couldn't see how he did it in such a tight, neat little package. Thanks, RetroACTIVE. Didn't see that purple wire.
edit: I still don't see any purple wire.
I'm attempting to crimp connectors onto the pins. I might solder them on. We'll see how it goes. I could do it another way altogether, I just like the way this looks.
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edit: I still don't see any purple wire.
...maybe I'm imagining it... though I saw it earlier... very faintly. Can't see the darn thing anymore cause I'm at work... (internet clamp!)
I'm recalling from my pea-brain... but the 12 v line is not used right?... So maybe in the pic... the person didn't clip the post off the header (yet)... and ran a jumper from left to right (connecting +5 to the old +12)....
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Hmmm...maybe. I'm still working on it.
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That's a header adapter and not an IC socket, yes? I think the swap is in the harness that connects to this adapter. You can't see it because it isn't there in the pic.
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That's a header adapter and not an IC socket, yes? I think the swap is in the harness that connects to this adapter. You can't see it because it isn't there in the pic.
It's both the header and the socket. Here's what I came up with:
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It needs testing, of course, but I believe it should work.
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Oops! I screwed up. Glad I looked at the schematic once more. I bridged the 12V Unreg to the +5. Have to more the bridge over one pin.
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Fixed now. Doesn't exactly like to go over the pins. Will have to try harder on my next one.
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I can confirm my adapter works. I tried it on my Stargate board, and it booted to garbage. But it didn't blow up.
Then I moved it to my Defender. I'd bought a lot of 4164 RAM off a guy I found on a Google search. It's the same 4164 I put in the Stargate board. I pried all the 4116 out and replaced it with the 4164.
It came up! But with a RAM error. I double checked to see if I screwed up inserting any, and sure enough I found one with a leg bent underneath. Replaced that with one of the spares I bought (lucky I got extras!) and it came up again, again with a RAM error. This time I was able to pinpoint which one with the onboard RAM test. Replaced that with another spare. This time it booted to garbage. Replaced it with yet ANOTHER spare, and it came up and passed all RAM tests! Yay, I have my Defender back!
This also gives me hope that one or two of the 4164 that I put on the Stargate board are bad since it also booted to garbage. Unfortunately it's impossible to determine which one.
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Old thread bump, but I thought I'd share an adapter I made today to pull off this memory swap.
Works great. My Defender is much more reliable now.
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I've just made my own 4164 RAM wiring adapter and blogged about it here: http://goo.gl/0mV0ud (http://goo.gl/0mV0ud). It was a fun project and, most importantly, it works!
The real tricks for me were:
1. Finding the connectors that would mate properly with the existing power connectors.
2. Figuring out if any RAM would do, or if you needed a particular type of 4164.
3. Not getting things backwards or reversed... It happens surprisingly easily...
Enjoy...
Craig